Page:Report from the Select Committee on Steam Carriages.pdf/203



Mr. J. McAdam. 25 August, 1831. goes, has any thing to do with the wear of the road, or is it not actually less injurious in proportion to its velocity?—In some instances where any blow takes place the speed does more injury to the road by crushing the materials.

You did not contemplate the general use of Vans, when that Act was drawn up?—No; not that they would come into such general use.

What proportion of the injury to the road do you think takes place from the changes of the atmosphere; frost and wet, has it any material effect?—Yes, decidedly, in chalk soils in particular; at Royston and through that country a great and serious injury takes place upon the breaking up of all frosts, nor can we, by any care or attention or strength of surface of the road prevent that taking place; it comes in a very eccentric manner and breaks up one year at one part of the road, and another at another, occasioned in a great measure by the standing of the water in the subsoil; and I suppose also, by the way in which the wind is at the time it freezes. It is the modern practice of road making to abstain from all general repair of the roads from the middle of April until the middle of October; during that period the only repairs that ought to take place are partial coatings, necessary from accidental circumstances. As soon after the middle of October as possible the general coating takes place in pieces of the road at a time, so as to interfere and interrupt as little as possible with general travelling, and we endeavour, by the month of February, to have the whole of the coatings put on; in no instance above a sixth part at a time.

On your line the Committee find, that the course of horizontal traction varies from 42 to 140, with these remarks, in the case of 42 "granite surface of many years standing," and the 140 "smooth surface road made of broken granite;" can you explain why such a difference should take place, both being smooth surfaces?—I am quite unable to account for it; no coatings of dirt upon a granite road ought to have produced so great a difference.

Have you witnessed the operation of a Carriage